Folding blade propeller

ABSTRACT

A foldable marine propeller assembly is disclosed having a pair of interengaged housing members that are releasably secured together by fasteners, locking the blade mounting swivel pin in blind sockets when so fastened, and that cooperatively define a recess for the securement nut to a drive shaft extending into the housing, the nut being retained against rotation.

United States Patent [191 l] 3,709,634

Lorenz 1 Jan. 9, 1973 1541 FOLDING BLADE PROPELLER 3,591,311 7/1971 Butler ..4l6/l42 [75] inventor: 3dr: L. Lorenz, Grand Rapids, FOREIGN PATENTS 0 APPLICATIONS 1c 26,090 11/1909 Great Britain ..416/i42 [73] Assrgnee: Michigan Wheel Corporation, Grand 154,495 12/1920 Great Britain ..416/l42 Rapids, Mich. Primary ExaminerEverette A. Powell, Jr.

{22] Flled' 1971 Attorney-Price, Heneveld, Huizenga & Cooper [21] Appl. No.: 108,000

[57] ABSTRACT [52] US. Cl ..4l6/l42 A foldable marine P p assembly is disclosed [51] Int. Cl. ..B63h 1/24 8 a P of interengaged housing members that F 581 Field or Search ..4l6/l42, 140 releasably Secured together by fasteners, locking blade mounting swivel pin in blind sockets when so [56] References Cited fastened, and that cooperatively define a recess for the securement nut to a drive shaft extending into the UNITED STATES PATENTS housing, the nut being retained against rotation.

3,255,826 6/1966 Beck ..416/l42 x 4 Claims, 11 Drawing Figures PATENTED R 9 I975 SHEET 1 UF 3 FIG. 2

o; M 2 & m; 4 u m 5 ATTORNEYS PATENTEBJAN 9191s 3,709,634

SHEET 2 or 3 INVENTOR 640a A. ZJPEA/ ATTORNEYS PATENTEU JM 9 I975 SHEET 3 OF 3 FIG. l0

FIG. I I

FIG. 8

INVENTOR AflP'A/Z ATTORNEY5 FOLDING BLADE PROPELLER BACKGROUND OF THE INVENTION This invention relates to marine propellers, and more particularly to a foldable marine propeller assembly.

Foldable marine propellers, as known for decades, employ a pair of blade elements that swivel between a radially protruding functional position and a trailing, axially oriented collapsed position. The principle is relatively simple. The difficulties arise in creating such an assembly which can be effectively secured to an engine drive shaft, which has the blades mounted securely, which enables rapid simple blade change, but which is yet streamlined in configuration, and has only a few simple parts to manipulate when blade changing is attempted. Known foldable prop assemblies are commonly characterized by their ineffectiveness in achieving all of these desirable characteristics in one assembly. Rather, the conventional housing is complex, bulky, and irregular, and/or the swivel pin for the blades is secured by troublesome cotter keys or pins or annular wedge rings, and/or the drive shaft securement is complex and unwieldy and often itself secured by cotter keys or pins, and other troublesome factors.

SUMMARY OF THE INVENTION It is an object of this invention to provide a novel foldable marine propeller assembly that does in fact provide all the noted sought-after features in the same unit. It can be effectively secured to a drive shaft, yet has a simple securement nut arrangement not employing cotter keys. The blades are mounted securely, without any cotter keys or the like, and also can be changed easily and quickly. It has only a few simple parts that can be readily manipulated. The housing is not bulky, but is thin and streamlined. The swivel pin mounting the blade elements is specially retained by the blind sockets in a pair of interengaged housing members. The cooperative elongated housing members are releasably secured together by fasteners, retaining the nut that attaches to the drive shaft from rotating relative to the housing.

These and other related objects, advantages, and features will be apparent upon studying the following specification along with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the novel foldable marine propeller assembly;

FIG. 2 is an elevational view of the assembly in FIG. 1, but shown with the blade in collapsed trailing condition;

FIG. 3 is a plan view of the assembly in FIG. 2;

FIG. 4 is a sectional view taken on plane lV-lV of FIG. 2;

FIG. 5 is a sectional view taken on plane VV of FIG. 2;

FIG. 6 is a plan view of one of the blade elements;

FIG. 7 is an elevational view of the blade element in FIG. 6;

FIG. 8 is an elevational view of one housing member;

FIG. 9 is an end elevational view of the member in FIG. 8;

FIG. 10 is an elevational view of the second housing member; and

FIG. 11 is an end elevational view of the member in FIG. 10.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now specifically to the drawings the complete marine foldable propeller assembly 10 basically includes a housing subassembly l2 composed of a pair of housing members 14 and 16 which are secured together by a plurality of fasteners 18, and two propeller blade elements 20 and 22 attached to the housing by a swivel pin 24. The assembly also includes other elements and features described in detail hereinafter.

Housing 12 is axially elongated, being formed of the two cooperative housing members 14 and 16. Housing member 14 has a nose portion 14a (FIG. 8) of generally annular cross-sectional configuration, and integrally attached rearwardly extending portions 14b and 14b that form a chordal segment of the rear portion of the housing. The remainder of the annular central section of the housing is formed by housing member 16, and particularly portion 16a thereof. Member 16 also includes a rearwardly extending chordal segment 16b integral with portion 16a. Thus, the central section of housing member 14, i.e., portion 14b, cooperates with portion 16a of member 16 to form a generally annular central portion of the total housing 12. This occurs when the front transverse face of member 16 is abutted against the rearward transverse face 14c of portion 14a and the upper edges 16d of portion 16a are engaged against the chordal face 14d of portion 14b.

The forward portion 14a of housing member 14 defines an axially extending, rearwardly converging, tapered, elongated socket 30 for receiving the rear terminal end of a drive shaft 44 from an engine (not shown). This socket includes an axially extending key slot 32 to keep the housing from rotating relative to the drive shaft. At the opposite axial end of the housing, members 14 and 16 define a slot 34 which extends clear through the opposite surfaces of the housing, between portions 16b and portions 14b. Each of housing members 14 ad 16, and specifically portions 14b and 16b thereof, defines a blind pin receiving socket 14e and 16:: respectively. These sockets are open toward slot 34, inwardly of the housing, are aligned with each other, and do not extend through the outer surface area of the housing members. Swivel pin 24 has its end received in and retained by the dead end or blind sockets (FIG. 4).

Mounted on swivel pin 24 are the two blade elements 20 and 22. More specifically, pin 24 extends through the aligned openings 39 of the flattened bosses 20a and 22a of blade elements 20 and 22. These blade elements can swivel from an operative position where the blade 20b and 22b extend radially and opposite to each other transversely of the axis of the housing and drive shaft, to a second trailing position, with the blades in engagement with each other, axially to the rear of the housing as in FIGS. 2 and 3. Pivotal movement of the blade elements back from this folded condition to the extended radial operative condition is limited by engagement of bosses 20a and 22a with the forward end of slot 34 of the housing.

At the inner end of the axially extending, drive shaft receiving socket 30 is an enlarged recess 40 formed by cooperative housing members 14 and 16 to receive a securement nut 42 that attaches to the rear terminal threaded end of drive shaft 44. This nut is prevented from rotating, once the housing is assembled, by a plurality of Allen socket screws 18 which also secure the two housing members together, and by the recess configuration. These screws 18 extend diagonally adjacent the faces of this hexagonal nut 42. The heads of the screws are recessed into housing member 16, with the threaded inner ends of the screws extending into threaded sockets in member 14.

Assuming the assembly is complete and is mounted to a drive shaft 44 as in FIGS. 2 and 3, dis-assembly is as follows. Socket screws 18 are threadably removed, enabling housing member 16 to be separated from the assembly. This exposes one terminal end of swivel pin 24, allowing its removal as well as removal of either or both of blade elements 20 and 22. The blades can thus be readily substituted by another set of blades, or the like, followed by return of the housing member 16 to its position and reattachment of screws 18. If it is desired to remove the assembly from drive shaft 44, this is done by readily loosening nut 42 to back it off its engagement with the annular shoulder formed by face 140 at the inner end of socket 30, removing the nut from the drive shaft, and sliding the housing off the end of the drive shaft.

Mounting of the structure on a drive shaft is just as simple. Specifically, housing member 14 is slid over the drive shaft rear terminal end with the drive shaft key inserted in key slot 32, nut 42 is threadably attached to the drive shaft and tightened against shoulder 14c, pin 24 and a pair of blades are inserted into member 14 with one end of the pin placed in blind socket l4e, and member 16 is positioned with its blind socket 16e over the second end of pin 24 and screws 18 are attached. The unit is ready for operation. Powered rotation of shaft 44 causes the blade elements to pivot outwardly into operative position by a combination of centrifugal force and water thrust on the rear faces of the blades. Removal of power from shaft 44, when under operation for example, causes the blades to automatically fold to the collapsed streamlined position to the rear.

Anyone familiar with this art will be able to readily appreciate the simplicity and functional capabilities of this novel structure. it is conceivable that certain minor details of this construction could be modified to suit a particular type of situation, while employing the concept set forth. Hence, it is intended that the invention is to be limited only by the scope of the appended claims and reasonable equivalents thereto, rather than by the details of the structure set forth as illustrative of the invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

l. A foldable marine propeller assembly comprising:

a pair of blade elements, each having a blade on one end and a fattened boss with a swivel opening on the opposite end; a swivel pin extending through said blade element openings; said blade elements being configurated and arranged to swivel on said swivel pin from a collapsedposition adjacent each other 0 a functional position protruding away from each other; the improvement comprising:

a pair of elongated housing members configurated to be interengaged to form an elongated housing having a streamlined outer surface area, and two axial ends; said housing members cooperatively defining a drive shaft receiving socket extending through one axial end of said housing, and defining an enlarged, drive shaft securement nut receiving recess at the inner end of said socket; a nut abuttment shoulder at the juncture of said socket and said enlarged recess; said housing members cooperatively defining a slot extending through said housing at the second end thereof, and receiving said flattened bosses; each of said housing members having a blind socket oriented transversely of said slot and transversely of said housing axis; said blind sockets being aligned with each other, opening into said slot, receiving the ends of said swivel pin, and being unexposed to said housing outer surface area; and fastener elements releasably securing said housing members in cooperative engagement to retain said swivel pin and blade elements.

2. The foldable marine propeller in claim 1 including a drive shaft securement nut in said receiving recess, locked against rotation therein.

3. The foldable marine propeller in claim 2 wherein said fastener elements are recessed into said housing outer surface area.

4. A foldable marine propeller assembly comprising:

a pair of blade elements, each having a blade on one end and a flattened boss with a swivel opening on the opposite end; a swivel pin extending through said blade element openings; said blade elements being configurated and arranged to swivel on said swivel pin from a collapsed position adjacent each other to a functional position protruding away from each other; the improvement comprising:

a pair of elongated housing members configurated to be interengaged to form an elongated housing having a streamline outer surface area, and two axial ends; said housing members cooperatively defining a drive shaft receiving socket extending through one axial end of said housing; said housing members cooperatively defining a slot extending transversely of the housing at the second end thereof, and receiving said flattened bosses; each of said housing members having a blind socket oriented transversely of said slot and transversely of said housing axis; said blind sockets being aligned with each other, opening into said slot, receiving the ends of said swivel pin, and being unexposed to said housing outer surface area; and fastener means releasably securing said housing members in cooperative engagement to retain said swivel pin and blade elements. 

1. A foldable marine propeller assembly comprising: a pair of blade elements, each having a blade on one end and a fattened boss with a swivel opening on the opposite end; a swivel pin extending through said blade element openings; said blade elements being configurated and arranged to swivel on said swivel pin from a collapsed position adjacent each other to a functional position protruding away from each other; the improvement comprising: a pair of elongated housing members configurated to be interengaged to form an elongated housing having a streamlined outer surface area, and two axial ends; said housing members cooperatively defining a drive shaft receiving socket extending through one axial end of said housing, and defining an enlarged, drive shaft securement nut receiving recess at the inner end of said socket; a nut abuttment shoulder at the juncture of said socket and said enlarged recess; said housing members cooperatively defining a slot extending through said housing at the second end thereof, and receiving said flattened bosses; each of said housing members having a blind socket oriented transversely of said slot and transversely of said housing axis; said blind sockets being aligned with each other, opening into said slot, receiving the ends of said swivel pin, and being unexposed to said housing outer surface area; and fastener elements releasably securing said housing members in cooperative engagement to retain said swivel pin and blade elements.
 2. The foldable marine propeller in claim 1 including a drive shaft securement nut in said receiving recess, locked against rotation therein.
 3. The foldable marine propeller in claim 2 wherein said fastener elements are recessed into said housing outer surface area.
 4. A foldable marine propeller assembly comprising: a pair of blade elements, each having a blade on one end and a flattened boss with a swivel opening on the opposite end; a swivel pin extending through said blade element openings; said blade elements being configurated and arranged to swivel on said swivel pin from a collapsed position adjacent each other to a functional position protruding away from each other; the improvement comprising: a pair of elongated housing members configurated to be interengaged to form an elongated housing having a streamline outer surface area, and two axial ends; said housing members cooperatively defining a drive shaft receiving socket extending through one axial end of said housing; said housing members cooperatively defining a slot extending transversely of the housing at the second end thereof, and receiving said flattened bosses; each of said housing members having a blind socket oriented transversely of said slot and transversely of said housing axis; said blind sockets being aligned with each other, opening into said slot, receiving the ends of said swivel pin, and being unexposed to said housing outer surface area; and fastener means releasably securing said housing members in cooperative engagement to retain said swivel pin and blade elements. 